溴酸钾催化氧化结晶紫-茜素红光度法测定废水中痕量铬(Ⅵ)

来源期刊：冶金分析2010年第12期

论文作者：贾华丽 李艳霞 王丽品

文章页码：74 - 76

关键词：铬(Ⅵ)； 催化光度法； 双波长； 双指示剂； 结晶紫； 茜素红

Key words：chromium (Ⅵ)； catalytic spectrophotometry； dual-wavelength； dual-indicator； crystal violet； alizarin red

摘    要：在H₂SO₄介质中,痕量铬(Ⅵ)能催化溴酸钾氧化结晶紫和茜素红褪色的指示反应,通过测量627 nm和423 nm处催化反应体系和非催化反应体系吸光度的变化,建立了双波长双指示剂催化动力学光度法测定痕量铬(Ⅵ)的新方法。方法的线性范围为0.04～0.16μg/mL,检出限为11.41 ng/mL。该方法用于电镀废液中铬(Ⅵ)的测定,测定值与原子吸收分光光度法测得结果一致,加标回收率为98%～102%。

Abstract: Trace chromium(Ⅵ) could catalyze the oxidation reaction of crystal violet-alizarin red by potassium bromate in H₂SO₄ medium.A new determination method of trace chromium(Ⅵ) by double-wavelength double-indicator catalytic kinetic spectrophotometry was established through studying the absorbance change of catalytic reaction system and non-catalytic reaction system at 627 nm and 423 nm.Linear range of this method was 0.04-0.16 μg/mL for chromium,and detection limit was 11.41 ng/mL.The proposed method has been applied to the determination of chromium(Ⅵ) in electroplating effluent.The results were in coincidence with those obtained by atomic absorption spectrometry with recoveries of 98%-102%.